Turbo-machine and method for operating the same

ABSTRACT

A turbo-machine having a rotor, a stator, and a flow channel for an actuating fluid used to drive the rotor is disclosed. The turbo-machine has a magnet for producing a predeterminable magnetic field in the flow channel. The invention also relates to a method for operating a turbo-machine comprising a rotor, a stator, and a flow channel. Furthermore, an ion-containing actuating fluid flows through the flow channel and a defined magnetic field is produced in the flow channel, ions being deviated in the magnetic field.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to the European application No.EP03000726.4, filed Jan. 13, 2003 and to the International ApplicationNo. PCT/EP2003/014417, filed Dec. 17, 2003 which are incorporated byreference herein in their entirety.

FIELD OF INVENTION

The invention relates to a turbomachine with a rotor and with a stator,a flow duct being formed for an action fluid by means of which the rotorcan be driven. The invention relates, furthermore, to a method foroperating a turbomachine with a rotor and with a stator and with a flowduct.

BACKGROUND OF INVENTION

Turbomachines are known, for example conventional steam turbines or gasturbines, in the forms of construction of which, normally, theconversion of energy takes place by means of what are known as bladecascades or blade wheels which drive the rotor of the turbomachine withan action fluid, for example steam or hot gas flows through theturbomachine. The blade cascades used in this case have the function, inthe flowing action fluid, of converting pressure energy into kineticenergy and converting kinetic energy into mechanical energy. These bladecascades are conventionally designed as moving blade cascades fastenedto the rotor or as guide blade cascades in the casing.

SUMMARY OF INVENTION

For the design of blade cascades of this type, particularly at hightemperatures of the action fluid flowing through the flow duct, it isnecessary to ensure flow optimization, but, in particular, also thestrength of, for example, the blade and blade fastening. There isparticular significance, in this context, in the fact that the strengthcharacteristic values of the high-temperature materials used decreasemarkedly at high temperatures. However, the aim is, in general, a higherprocess temperature, since this results in a rise in the thermodynamicefficiency of the turbomachine. This influence of the high operatingtemperature on the strength characteristic values of the materials usedapplies likewise to the rotors of thermal turbomachines.

In this case, in addition to the blades, the rotor is one of thecomponents subjected to the highest stress, especially since, when highmaterial temperatures are present, it is exposed to considerablecentrifugal forces. Rotor centrifugal forces act in this case both onthe rotor shaft and on the moving blades which are arranged on thecircumferential surface of the rotor shaft. Moreover, furtherhigh-temperature effects on blades or rotors are to be noted. Referencemay be made here, as an example, to high-temperature corrosion oroxidation. Blades for extremely high application temperatures, such as,for example, gas turbine blades, are therefore produced partially frommonocrystalline workpieces and, because of the high temperatures of theaction fluid, for example of the hot gas, need a considerable coolingrequirement. For this purpose, a coolant mass flow is provided, which,in the case of a gas turbine, is extracted, for example, from acompressor preceding the gas turbine, as compressor extraction air whichis routed through a complicated duct and bore system inside a hollowblade for cooling the blade (swirl, impact or film cooling). Inaddition, in the use of high temperatures in hot aggressive media,blades of this type require heat insulation layers for heat insulationand also corrosion protection layers. In this case, where gas turbinesare concerned, turbine application temperatures of the hot gas of 1200°C. and above are possible. Where steam turbines are concerned, thetypical process data amount, for example, to between 540° C. and 600° C.for the fresh steam temperature in the case of the fresh steam pressureof about 250 to 300 bar of the steam supplied to a conventionalhigh-pressure part turbine.

The conversion of pressure energy into kinetic energy and of kineticenergy into mechanical energy, using guide blade cascades and movingblade cascades with conventional blading, therefore has somedisadvantages. As a consequence of manufacture, the blades, of course,have a certain wall strength or thickness reducing the actual flow crosssection of the flow duct.

This effect is also designated as the obstruction effect. Furthermore,because of the finite number of blades, there cannot be an optimumhomogeneous deflection of the action fluid. In addition, blade cascadespossess a flow resistance, that is to say boundary layers are formed onthe blades, which may lead to secondary losses in the following bladecascades. As already discussed further above, because of the use ofhigh-grade high-temperature materials, blades for use inhigh-temperature applications are very costly and of limited strength onaccount of the increased material and manufacturing costs. Owing to thestrength aspects of the high centrifugal force loads on moving blades,the height of the blades, that is to say the maximum blade leaf length,is limited. In the event of a failure of a blade, for example as aresult of a breakaway from the rotor due to an overshooting of themaximum permissible centrifugal force load, considerable consequentialdamage may occur in the turbomachine. Thus, for example, in an axialturbomachine, in particular, the following blade cascades arranged inthe flow direction of the action fluid may be destroyed. A furtherdisadvantage of the known bladings is attributable to the gap losseswhich always occur. Gap mass flows of action fluid, which pass throughbetween a blade and component located opposite the blade so as to form agap, result in an efficiency loss (gap loss). In order to keep thelosses as low as possible, the gap mass flow must be limited by means ofnarrow clearances which are highly complicated to ensure inmanufacturing processes. In this context, a minimum clearance should notbe undershot for reasons of the operating reliability of theturbomachine. Gap losses of this kind were investigated, for example, inthe dissertation of Helmut Pollak “Experimentelle Untersuchungen derStrömungsvorgänge in axialen Kaltluftturbine unter besondererBerücksichtigung der Radialspaltströme und ihre Einflussparameter”[“Experimental investigations of the flow processes in axial cold-airturbines, with particular attention to the radial gap flows and theirinfluencing parameters”], Rheinisch/Westfälische Hochschule, Aachen.

The book “Kraftwerkstechnik zur Nutzung fossiler, regenerativer undnuklearer Energiequellen” [“Power station technology for the utilizationof fossil, regenerative and nuclear energy sources”] by K. Straus, 4thedition, Berlin, Heidelberg, Springer Verlag, 1998, pages 363-370,describes magnetohydrodynamic energy converters and power stationconcepts based on magnetohydrodynamic energy conversion. Themagnetohydrodynamic principle, as such, has been known for a long timeand, in the abovementioned literature reference, has already beenincorporated into concepts for power stations, that are known as “MHDpower stations”. The basis for magnetohydrodynamic energy conversion(MHD) is the principle of electromagnetic induction which is alsoutilized in the conventional dynamo machine. According to thisprinciple, a voltage is induced in an electrically conductive materialwhen the latter moves in relation to a magnetic field. In an MHDgenerator, an electrically conductive fluid flows through the magneticfield. The action of the magnetic field results, in the fluid, in aseparation of charges of opposite polarity and, consequently, in adirect conversation of potential energy of the plasma into electricalcurrent. Electrical conductivity is in this case a particularlyimportant property of the working medium in MHD generators. If the smokegases from the combustion of fossil fuels are to be used as workingmedium, these must be in the plasma state in order to be electricallyconductive. The atomic bonds of the electrons with the cores are brokenup in this state, the gas then consisting predominantly of freeelectrons and positively charged ions. The partial ionization of a gasis achieved by heating to very high temperatures higher than 2000° C.For practical reasons, conductivity should amount to at least 10 S/m. Incombustion gases, such values of this order of magnitude are reachedonly at temperatures of 2000 to 2500° C. by the addition of easilyionizable materials, such as caesium or potassium. On account of thefunctional principle provided for an MHD power station, however, it hasnot been possible to develop these power station concepts up toreadiness for use.

The principle of the MHD generator according to this concept is, bymeans of combustion with highly heated combustion air, to generate theplasma state, a state in which positive ions and electrons are presentin the gas, in a pressure-guiding combustion chamber. The hot plasma,when it emerges from the chamber, enters what is known as a diffuser. Inthis diffuser, the positive ions and the electrons are deflected bymeans of a magnetic field toward different electrodes where theelectrons are absorbed and the ions lose their charge due to theabsorption of electrons. A charge flux, that is to say a current, isthereby directly brought about. After emerging from the MHD generator,the gas is always still very hot, about 2300 K. For the furtherutilization of this heat energy available in the hot gas, the inflowingcombustion air is preheated to approximately 2100 K by means of heatexchangers. The remaining heat energy is supplied to a following steamprocess by means of conventional waste heat recovery boilers. Thisconcept entails considerable problems which have hitherto prevented itslarge-scale practical implementation:

Thus, for example, to achieve a plasma at 2500 K, the gas must beinoculated with easily ionizable substances (potassium, caesium), asalready described above. These alkali metals are costly and can behandled only with difficulty. Moreover, they lead to the contaminationand corrosive attack of the heat exchanger surfaces, such as areprovided in the air heater and in the waste heat recovery boiler.Furthermore, extremely high temperatures for achieving the plasma statepresent considerable challenges in terms of suitable high-temperaturematerials for the MHD generator. This also affects components of thediffuser and of the heat exchangers. Furthermore, it has to be said thatthe achievable efficiency of the currently known and used GUD powerstations has, in the meantime, been so high that a major increase inefficiency will be achieved only with great difficulty by means of thetechnology of MHD generators.

To that extent, preceding the steam power process with an MHD generator,which is difficult to implement in technical terms, competes with thesteam power process being preceded with a gas turbine which is alreadyproven and accepted on a large scale. However, difficult problems haveto be solved, even outside the actual MHD generator, on the way to acommercial MHD plant. Most of these problems are due to the hightemperature level in the plasma duct, for the construction of which allthe metal materials known hitherto are ruled out. Even where theelectrodes are concerned, erosion, corrosion and heat stresses limit theoperating time to less than 1000 hours. Despite intensive researchtherefore, the commercial implementation of an MHD plant cannot beforeseen at the present time.

In a summarizing assessment of the concept known hitherto, it may besaid that, in conventional gas turbines and steam turbines, the bladesand rotor, in addition to combustion chamber and boiler components, aresome of the most highly stressed components of turbomachines of thistype. Thus, in particular, the inlet blading is particularly affecteddue to the high temperatures of the hot action fluid. Thehigh-temperature strength of the blade materials in this case limitspossible application temperatures and, in part, requires technicallycomplicated cooling measures. For the manufacturers of gas turbines andsteam turbines, however, the increase in the upper process temperatureis an essential starting point for an increase in efficiency. Sometimesconsiderable efforts to raise the upper process temperature can beobserved both in the area of gas turbine technology and in that of steamturbine technology. By contrast, the use of the magnetohydrodynamiceffect in the MHD power stations described above has not had anylarge-scale application hitherto because of insufficientimplementability, above all because of the disadvantageous principle ofaction and technological difficulties.

An object of the invention is to specify a turbomachine which avoids thedisadvantages of the concept described above.

A further object of the invention is to specify a method for operating aturbomachine.

The first mentioned object is achieved, according to the invention, bymeans of a turbomachine with a rotor and with a stator, a flow ductbeing formed for an action fluid by means of which the rotor can bedriven, a magnet being provided which serves for generating apredeterminable magnetic field in the flow duct.

The invention describes an entirely novel concept for a turbomachine, inwhich the magnetohydrodynamic effect is applied in order to deflect theflow medium within turbomachines, instead of blade cascades. It thusbecomes possible to implement an “MHD turbine” or an “MHD compressor”.The magnetohydrodynamic effect causes a deflection of electricallycharged particles of a flow medium in the flow duct of the turbomachine.To generate a defined magnetic field, the magnet is provided, whichdeflects charged particles in the action fluid according to Lorenz forcedeflection. When the electrical charge is moved at a specific velocityin a predetermined magnetic field, described as magnetic induction, theelectrical charge experiences a force. This force is alwaysperpendicular to the velocity. Charged particles in the action fluidflowing through the flow duct therefore experience a deflection due tothe defined magnetic field generated by the magnet, insofar as themagnetic field has at least one component perpendicular to the directionof movement of the charged particles, that is to say to the flowdirection of the action fluid. In the ideal situation of an infinitelyextending homogenous magnetic field, charged particles are forced onto acircular path. When they race through a finite, that is to say spatiallydelimited magnetic field, the particles therefore follow an arc of acircle. This effect is utilized, according to the invention, in order todeflect the action fluid itself in a flow duct of a turbomachine.

By means of the magnet, a both time-defined and spatially-definedmagnetic field can be generated in the flow duct, thus leading to adefined deflection of charged particles in the action fluid and, onaccount of a pull effect as a result of pulse transfer, to a deflectionof the action fluid itself. Deflection in this case takes placeadvantageously in the form of deflection planes between rotor and statorwhich are predetermined by the magnetic field and which possess alimited extent (localization of the magnetic field) in the main flowdirection of the action fluid, for example in the axial direction in thecase of an axial machine. The provision of a magnetic deflection planefor the charged particles or the action fluid by means of the magneticfield is very similar in its action to a conventional blade cascade:where an axial turbomachine is concerned, for example, a deflection of apredominantly axial flow of the action fluid takes place in a flow withboth an axial and a tangential component, this being because of the factthat, on account of the Lorenz force, a tangential component is impartedto the charged particles perpendicularly to the flow direction as aresult of the interaction with the magnetic field. This deflection isassociated with a conversion of pressure energy of the action fluid intokinetic energy, in a similar way to a guide blade cascade of aconventional turbine. In the same way, it is possible, from a flow ofthe action fluid with an axial and tangential component, to achieve aconversion into a predominantly axial flow, with kinetic energy beingconverted into mechanical work, in a similar way to a moving bladecascade of a conventional turbine. Consequently, in a similar way toconventional turbines, a suitable magnetic field configuration, with amagnetic field in the flow duct is generated spatially and, ifappropriate, in time by means of the magnet, makes it possible to have aprogressive expansion of the action fluid, at the same time with theacquisition of mechanical work which can be transmitted in the form ofrotational energy to the rotor.

By virtue of the invention, in this case, advantageously, the functionof the deflection of the flowing action fluid, which, at hightemperatures, can be implemented only at considerable cost or not at allby means of conventional blades, continues to be ensured, but, here, isachieved by means of a magnetic field or by means of magnetic fields, ascompared with conventional turbine technology. In this case, theinvention advantageously combines the known functional principle ofconventional turbomachines with the deflection effect of a magneticfield on charged particles. At the same time, the specific disadvantagesof the MHD power station concept can be avoided, because a thermalgeneration of a plasma at extremely high temperatures is not absolutelynecessary for operating the turbomachine. In contrast to an MHDgenerator, not even direct current generation by charge deflection onelectrodes is adopted, but, instead, mechanical energy in the form ofrotational energy of the rotor is generated during the expansion of theaction fluid in the turbomachine. It is thereby possible, in thedevelopment of novel gas turbine and steam turbine technologies with theconcept of the turbomachine, to achieve markedly high processtemperatures, thus leading to an increase in the thermal efficiency ofthe turbines. The application of a novel advantageous type offunctioning for turbomachine construction is thereby possible, and, inthis context, fundamental improvements may be expected.

In a preferred embodiment of the turbomachine, the stator has themagnet. In this case, it is possible to integrate the magnet into thestator, so that the magnetic field generated by the magnet acts into theflow duct. In this case, it is also possible for the stator to have aplurality of magnets, so that the magnetic field can be set highlyaccurately in spatial terms in the flow duct according to therequirements. In the case of an axial machine, in which the statorconventionally at the same time forms an outer boundary of the flow ductand at the same time can function as an outer casing of theturbomachine, the magnet is advantageously particularly readilyaccessible for possible maintenance or inspection work or for themounting of sensors (for example, magnetic field sensors) for thediagnostics of the turbomachine. Furthermore, if a ferromagneticsubstance is selected, the stator material may at the same time be usedfor increasing the magnetic flux density and consequently the magneticfield in the flow duct.

In a particularly preferred embodiment of the turbomachine, the magneticfield is directed radially and has at least one sign change along theaxis of rotation of the rotor with respect to the radial direction.

A radial magnetic field can be generated, for example, by means of amagnet mounted on the stator, the magnetic field extending radiallyinward through the flow duct into the rotor. The sign change of theradial magnetic field component along the axis of rotation affords atleast one region in the flow duct in which the flux lines of themagnetic field run, for example, radially inward from the stator to therotor, and at least one second region in the flow duct in which fluxlines emerge from the rotor, extend radially outward through the flowduct and enter the stator. Thus, with respect to the radial direction,there is an opposite sign of the magnetic field in the second region towhat is the case in the first mentioned region. By means of the signchange of the magnetic field, it is possible to deflect chargedparticles in the flow duct in mutually opposite directionsperpendicularly to the direction of movement of the charged particles,that is to say of the action fluid. Where an axial turbomachine isconcerned, it is beneficial to provide at least one sign change of themagnetic field, so that along the axis of rotation of the rotor thereare at least two different spatial regions with a magnetic field ofdifferent sign. During the movement of a charged particle along theaxial direction of the turbomachine, therefore, a tangential deflectiontakes place in the first region, for example clockwise, while, in thesecond region, the charged particle experiences a force in the oppositedirection, for example counterclockwise.

The functional principle of the turbomachine will be presented in amodeled manner by means of the following simplified methods ofconsideration: thus, the flux lines of the deflection magnetic field aretaken into account only in their main direction of action, that is tosay radially between rotor and stator, that is to say there is anidealized consideration of essentially parallel magnetic flux lineswhich are directed either radially inward or radially outward. Thissimplification therefore ignores dispersion influences and theireffects, as should be permissible in the framework of an illustration ofthe fundamental principle. Furthermore, as compared with theconsideration of the gas dynamics which consider the thermal movement ofthe particles within equal distribution in all directions of space, themovement of the ions is taken into account only with regard to thefraction which arises from the approach flow of the action fluid. Theapproach flow of the action fluid is superimposed on the thermalmovements which are assumed to be distributed essentially equally. Tothat extent, the consideration of the deflection effect weighs up, as astatistical average, the velocity of the flowing action fluid which issuperposed on this equal thermal distribution.

When entering a magnetic field generated in a defined manner in the flowduct radially between the rotor and stator by means of the magnet,electrically charged particles present in the flowing action fluid aredeflected by the magnetic field. It is presupposed, here, that the mainflow direction of the action fluid is the axial direction, as is thecase, for example, in an axial turbomachine. Thus, there acts on thecharged particles a force which is dependent on the magnetic fluxdensity in the flow duct and on the velocity and charge of the particlesand which is directed perpendicularly to the direction of movement. Thisdeflection force is also designated as the Lorenz force. The chargedparticles in question are either electrons with a comparatively low massand with a negative elementary charge or singly or multiply chargedpositive ions with a markedly higher mass. On account of different signsfor the charged particles, the electrons are deflected in the oppositedirection to the positive charged ions. Due to the marked differences inmass (about the factor 10⁴), moreover, the electrons are forced onto amuch smaller circular path than the ions. When the radial magnetic fieldis set in such a way that the ions, when running through the magneticfield, experience a deflection which corresponds in its action to thedeflection caused by a conventional blade cascade, then the electronsare consequently pulled onto a very much smaller circular path, theradius of which is generally smaller than the axial extent of the radialdeflection field. The electrons therefore do not, like ions, leave themagnetic field with an accurately directed well defined deflection, but,instead, pass onto a circular path with a markedly smaller radius or ahelical path, depending on the original direction and velocity on entryinto the magnetic field. Moreover, as a result of collisions betweenelectrons and other particles of the action fluid, changes in thetrajectory and, if appropriate, in the velocity of the electrons occur,so that these can ultimately likewise leave the magnetic field. As aresult of the accurately directed deflection of the ions provided with acomparatively high mass at a specific circumferential angle when theyrun through a region of the flow duct flooded with a magnetic field, inparticular with a radial magnetic field, on the one hand, and of theessentially diffuse emergence of the markedly lighter electrons which isbrought about by collision processes, on the other hand, an angularmomentum is transmitted in the action fluid having the chargedparticles. Thus, depending on the spatial arrangement, intensity andsign of the magnetic field in the flow duct generated by the magnet,different deflection effects, that is to say a different transmission ofangular momentum to the action fluid, can be set in terms of amount andof direction.

Preferably, an axially extending magnetic guide blade region with aconstant sign of the magnetic field and an axially extending movingblade region with a sign of the magnetic field which is opposite to thatof the guide blade region are provided.

In the magnetic guide blade region, an increase in the flow velocityoccurs due to the deflection of the action fluid flowing in the axialdirection, in a similar way to conventional turbine guide bladecascades. In this case, a tangential fraction is superposed from theaxial main flow direction, a conversion of pressure energy into kineticenergy taking place. The magnetic guide blade region in this case has adefined sign of the magnetic field, that is to say radially inward orradially outward in the entire guide blade region. The magnetic guideblade region is in this case, in spatial terms, a part region of theflow duct. However, the intensity of the magnetic field may perfectlywell vary within the magnetic guide blade region, but is preferablyvirtually constant. The magnetic guide blade region therefore defines,as it were, a deflection plane functioning as a guide blade cascade or adeflection disk which extends in the axial direction and which,considered in abstract, exerts on the action fluid an action which isequivalent to a conventional turbine guide blade cascade.

Similarly, a deflection of the largely axially directed flow of theaction fluid takes place in the magnetic moving blade region, in such away that the angular momentum extracted from the medium is transmittedto the rotor of the turbomachine. The magnetic field is in this casedirected essentially radially in the magnetic guide blade region and inthe magnetic moving blade region. The magnetic guide blade region andthe magnetic moving blade region in this case form, for example,spatially different part regions of the flow duct. In this embodiment,the deflection of the action fluid in the turbomachine, for example inthe form of deflection planes or deflection disks spatially delimited inthe axial direction, takes place by means of a radially directeddeflection magnetic field which extends through the flow duct betweenthe stator and rotor. Owing to the extent (deflection disk or deflectionplane) delimited spatially in the flow direction of the action fluid,the action of the magnetic guide blade region and the magnetic movingblade region is very similar to the action of blade cascades inconventional turbomachines, for example gas turbines, steam turbines orcompressors. There is in this case a deflection of the predominantlyaxial flow into a flow with an axial and tangential component, pressureenergy being converted into kinetic energy. The magnetic guide bladeregion is to that extent to be conceded as similar to a guide bladecascade of a conventional turbine in terms of the fundamental type ofaction. In the magnetic moving blade region, a deflection of a flow withan axial and tangential component into a predominantly axial flow takesplace, kinetic energy being converted into mechanical work. This effectis essentially similar to the action of a moving blade cascade of aconventional turbine. Advantageously, by a suitable arrangement ofsuccessive magnetic guide blade regions and moving blade regions, anexpansion of the working fluid which is progressed in a similar way toconventional turbines can be achieved, at the same time with mechanicalenergy in the form of rotational energy of the rotor being acquired.

Preferably, therefore, the magnetic moving blade region follows themagnetic guide blade region axially in the flow direction of the actionfluid. A step is thereby produced in a similar way to a conventionalturbomachine with a guide wheel and with a moving wheel. The magneticstep of the turbomachine in this case has a magnetic guide blade regionand a magnetic movement blade region adjoining the latter axially. Themagnetic moving blade region does not in this case have to directlyadjoin the magnetic guide blade region in the flow direction. Betweenthe magnetic guide blade region and the axially following magneticmoving blade region, the flow duct may be field-free or be essentiallywithout an appreciable magnetic field. In an intermediate region of thiskind, takes place then virtually no further deflection of the chargedparticles and, consequently, no further transmission of angular momentumto the flowing action fluid having the charged particles.

Preferably, a number of magnetic guide blade regions and moving bladeregions are arranged alternately along the axis of rotation. A pluralityof magnetic steps, that is to say a plurality of magnetic guide bladeregions and of magnetic moving blade regions arranged alternately onebehind the other axially, that is to say along the axis of rotation, canthus be implemented in the turbomachine. This, too, may again be seen asbeing somewhat analogous to the known turbomachines with a plurality ofsteps arranged axially one behind the other. Depending on requirements,therefore, turbomachines can be designed with a different number ofsteps and a different step size, in each case comprising a magneticguide blade region and a magnetic moving blade region adjoining thelatter.

Preferably, in order to delimit the magnetic field in the magnetic guideblade region, the magnetic guide blade region comprises a radiallyinwardly extending projection of the stator. By means of the radiallyinwardly extending projection, a local increase in the magnetic fluxdensity is achieved, that is the magnetic flux lines are concentrated inthe space between the projection and the rotor located opposite theprojection inwardly in the radial direction. By virtue of thisconfiguration, approximately, a magnetic dipole structure is producedlocally, in which case, depending on the selected polarity, for example,magnetic flux lines emerging from the projection form a magnetic northpole, while the opposite rotor surface which the magnetic flux linesenter forms a south pole. The spatial confinement of the field allows anaccurately directed deflection of charged particles in the action fluid,so that, analogously to a conventional turbomachine, a guide blade isproduced, the principle of action of which is, however, based on themagnetic deflection of charged particles.

However, as compared with conventional blading, in the magnetic guideblade of the invention there is advantageously no need for any complexgeometry for the projection. The projection may be configured, in termsof its geometry and its magnetic properties of the material, in such away that the best possible results are achieved, in a similar way to apole piece. The projection may in this case be adapted in aconstructively simple way to the radial symmetry, in particular to thecylinder-envelope-shaped surface contour of the rotor, and consists of amaterial with high magnetic permeability, in order to achievecorrespondingly high magnetic flux densities of the radial deflectionmagnetic field.

In a preferred embodiment, in order to axially delimit the magneticfield in the magnetic guide blade region, the stator has a radiallyinwardly extending circumferential ring in which the projection isarranged. The circumferential ring extends over the entire circumferenceabout the axis of rotation of the rotor. The axial extent of thecircumferential ring in this case determines essentially also the axialextent of the magnetic field. As a result of the axial and radialconfinement, a magnetic deflection plane, more precisely a magneticdeflection disk on account of its axial dimension, is produced in themagnetic guide blade region, in a similar way to a guide blade row orcascade in a conventional turbomachine.

For this purpose, in a preferred embodiment, a plurality of radiallyinwardly extending projections are arranged over the entirecircumference of the stator. The multiplicity of projections achieves,over the entire circumference, an identically acting and thereforereinforced deflection of the flow medium, spatial regions with a highmagnetic field intensity being formed correspondingly to the number andarrangement of the projections. For reasons of symmetry, the projectionsare advantageously distributed regularly over the entire circumferenceof the stator, for example along an imaginary regular polygon. In thiscase, an embodiment of the circumferential ring, as described above, onwhich a plurality of projections are arranged, is particularlybeneficial for radial and axial field confinement.

With regard to the magnetic moving blade region, this particularlypreferred embodiment comprises a radially outwardly extending projectionof the rotor in order to delimit the magnetic field spatially. Theadvantages of this configuration arise in a similar way to the magneticguide blade region:

The radially outwardly extending projection achieves a local increase inthe magnetic flux density, that is to say the magnetic flux lines areconcentrated in a space between the projection and the stator locatedopposite the projection in a radial direction. Owing to thisconfiguration, approximately, a magnetic dipole structure is implementedlocally, in which case, depending on the selected polarity, magneticflux lines emerging, for example, from the projection form a magneticnorth pole, while the opposite stator surface which the magnetic fluxlines enter forms a south pole. The spatial confinement of the fieldallows an accurately directed deflection of charged particles in theaction fluid, so that the moving blade based on the magnetic deflectionof charged particles is thereby intimated, in a similar way toconventional turbomachines.

Preferably, in this case, a plurality of radially outwardly extendingprojections are arranged over the entire circumference of the rotor. Themultiplicity of projections achieves, over the entire circumference, anidentically acting and therefore intensified deflection of the flowmedium, spatial regions with high magnetic field intensity being formedcorrespondingly to the number and arrangement of the projections. Forreasons of symmetry, the projections are advantageously distributedregularly over the entire circumference of the rotor, for example alongan imaginary regular polygon. In this case, an embodiment with acircumferential ring, as already described above in connection with themagnetic guide blade region, on which a plurality of projections arearranged, is particularly beneficial for radial and axial fieldconfinement.

Preferably, the turbomachine has an ionization device for the generationof charged particles in the action fluid. The ionization of neutralparticles in the action fluid may in this case take place in variousways by means of the ionization device, for example by collisionionization or by radiation ionization. A suitable ionization process, onthe principle of which the ionization device is to operate, must beselected, depending on the active cross section for the ionization ofspecific neutral particles. High temperatures, as in thermal plasmageneration, are advantageously not required in this case. Multipleionization is also possible. By means of the ionization device,therefore, an ion-containing action fluid can be generated or provided,which drives the magnetohydrodynamic turbomachine of the invention whenit flows through the flow duct.

Preferably, the turbomachine has a recombination device for therecombination of charged particles in the action fluid.

The object directed at a method is achieved, according to the invention,by means of a method for operating a turbomachine with a rotor and witha stator and with a flow duct, in which an ion-containing action fluidflows through the flow duct, and a defined magnetic field is generatedin the flow duct, ions being deflected in the magnetic field.

The advantages of the method arise in a similar way from the advantagesof the turbomachine described above.

Thus, in a preferred embodiment of the method, the rotor is set inrotation as a result of the deflection of ions due to interaction withthe magnetic field.

Also preferably, a radial magnetic field acting on the ions is generatedin the flow duct in such a way that the tangential velocity component ofthe ion-containing action fluid is influenced in an accurately directedmanner when the latter flows through the flow duct. The action of theLorenz force on the charged particles, that is to say the ions which aremarkedly heavier than the electrons, is in this case utilized in acontrolled way in order, as a result, to impart a net angular momentum(swirl) to the action fluid. The angular momentum transfer may lead toan increase in swirl or to a reduction in swirl of the flowing andexpanding action fluid.

Preferably, in a flow duct, a radial magnetic field is generated whichalternates along the flow direction of the ion-containing action fluid.In this context, alternating magnetic field means that, along the flowdirection, the radial component of the magnetic field has at least onesign change, that is to say a polarity reversal of the radial componenttakes place.

In a preferred embodiment of the method, the magnetic field is in thiscase regulated in time and/or spatially. This may take place, forexample, by means of a corresponding arrangement and electric activationof the magnet or magnets in order to generate a predeterminable fielddistribution in the flow duct.

Preferably, the ion-containing action fluid is formed by the ionizationof particles in the action fluid before the flow of the latter throughthe flow duct. This may be achieved, for example, by means of anionization device preceding the inlet orifice of the flow duct.

Also preferably, ions are formed by the ionization of particles in theaction fluid during the flow of the latter through the flow duct. Thein-situ generation in this case has the advantage that the ions can begenerated in an accurately directed manner in the regions where they arealso required for performing a magnetic deflection, that is to say inthe magnetic guide blade region or the magnetic moving blade region.

To generate the ions, these are preferably formed by collisionionization. Alternatively or additionally, ions are formed by radiationionization, action fluid being irradiated with a radiation having anionizing action on particles in the action fluid. This radiation may be,for example, UV radiation or X-ray radiation.

Preferably, the action fluid is purified of harmful substances in arecombination process and/or a catalytic process. Purification ispreferably carried out during and/or after the flow through the flowduct.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail by means of a drawing inwhich, in a simplified illustration not true to scale,

FIG. 1 shows a detail of a turbomachine based on a magnetohydrodynamicprinciple,

FIG. 2 shows a path curve of a charged particle in a spatially delimitedmagnetic field,

FIG. 3 shows a sectional view in the axial direction through a magneticguide blade region along the sectional line III-III of the turbomachineillustrated in FIG. 1,

FIG. 4 shows a sectional view in the axial direction through a magneticmoving blade region along the sectional line IV-IV of the turbomachineillustrated in FIG. 1,

FIG. 5 shows a graph of the pressure profile and velocity profile for aconventional turbine,

FIG. 6 shows, in comparison with FIG. 5, a graph of the pressure profileand velocity profile for a turbine with magnetohydrodynamic blading,

FIG. 7 shows a block diagram of the arrangement of the process functionsby the example of a steam turbine, using magnetohydrodynamic blading,and

FIG. 8 shows a block diagram of the arrangement of the process functionby the example of a gas turbine, using magnetohydrodynamic blading.

Identical reference symbols have the same meaning in the figures.

DETAILED DESCRIPTION OF INVENTION

FIG. 1 shows a detail of a turbomachine 1 which operates according to amagnetohydrodynamic principle. For this purpose, the turbomachine 1 hasa rotor 3 extending along an axis of rotation 11. A stator 5 surroundsthe rotor 3, so as to be spaced apart concentrically from the latter,over the entire circumference, thus forming an annular axial flow duct7, to which an ion-containing action fluid A, for example anion-containing steam or a gas, can be supplied. The rotor 3 can bedriven by the action fluid A when the latter flows through the flow duct7, magnetic deflection effects on charged particles 25, in particular onions 27, being utilized in an accurately directed manner in the actionfluid A.

For this purpose, the turbomachine 1 has a magnet 9 for generating apredeterminable magnetic field B in the flow duct 7. The magnet 9 isintegrated fixedly into the stator 5 and, for example, may beconfigured, as shown, as a magnet coil, the desired magnetic field B inthe flow duct 7 being achieved, in terms of its field intensity, by thesetting or regulating of an electrical current intensity through thecoil. Advantageously, due to this design, only stationary windings areused. In order to increase the magnetic flux density, the stator 5 inthis case consists at least partially of a ferromagnetic material. Therotor 3 is likewise produced from ferromagnetic material. As a result, agood magnetic field ring closure is achieved, and particularly high fluxdensities in the flow duct 7 are achieved precisely where theinteraction of the magnetic field B with the ions 27 is provided. Themagnetic field B is directed in the flow duct 7 essentially radially,that is to say perpendicularly to the main flow direction, parallel tothe axis of rotation 11, of the action fluid A charged with ions 27.Along the axis of rotation 11 of the rotor 3, the magnetic field B hasat least one sign change with respect to the radial direction, that isto say there is at least one polarity reversal. The magnetic fielddistribution is set in such a way that, as seen in spatial terms, anaxially extending magnetic guide blade region 15 with a constant sign ofthe magnetic field is formed in the flow duct 7. Furthermore, an axiallyextending magnetic moving blade region 17 with a sign of the magneticfield B which is opposite to that of the guide blade region 15 isprovided. Between the magnetic guide blade region 15 and the magneticmoving blade region 17, a virtually field-free interspace 35 is formed,in which no magnetic deflection of the charged particles 25 is to benoted. A magnetic moving blade region 17 in this case follows a magneticguide blade region 15 axially so as to form the axial interspace 35. Themagnetic field configuration thereby formed may be designated as amagnetohydrodynamic step or MHD step, in a similar way to a conventionalturbine step.

A number of such MHD steps are arranged in succession along the axis ofrotation 11, so that a corresponding number of magnetic guide bladeregions 15 and moving blade regions 17 are arranged in the turbomachine1 alternately along the axis of rotation 11 so as to form a respectivefield-free interspace 35. The interspace 35 is delimited radiallyinwardly, that is to say on the rotor side, and radially outwardly, thatis to say on the stator side, by a respective flow guide plate 33. Sincethe interspace 35 is desired to be field-free, the advantageousembodiment of the flow guide plate 33 is not made from a ferromagneticmaterial.

FIG. 2 shows, for explanatory purposes, a path curve 37 (trajectory) ofa positively charged ion 27 in a spatially delimited magnetic field B,such as is obtained, ideally, by means of the MHD blading in theturbomachine 1 of FIG. 1. In this case, a spatially delimited region 39with a magnetic field B is shown, which is delimited in the axialdirection by field-free regions 39A, 39B. Owing to the action of theLorenz force F_(L) on the charged ion 27 moving at the velocity v, adeflection in the region 39 perpendicularly to the magnetic fielddirection and perpendicularly to the direction of movement of the ion 27takes place, thus leading to a curved path curve 37 in the region 39. Bycontrast, no deflection takes place in the field-free regions 39A, 39B,that is to say the path curve runs in an essentially undisturbed manner,that is to say rectilinearly. This elementary field distribution of themagnetic field B and the action of said field distribution on a flowingexpanding ion-containing action fluid A is proposed by the concept ofthe invention for the first time in a turbomachine.

FIG. 3 shows, for a more detailed explanation, a greatly simplifiedsectional view in the axial direction through a magnetic guide bladeregion 15 along the sectional line III-III of the turbomachine 1illustrated in FIG. 1. The stator 5 surrounds the rotor 3 concentricallyso as to form the flow duct 7. To delimit the magnetic field B in amagnetic guide blade region 15, the magnetic guide blade region 15 has aplurality of radially inwardly extending projections 19 which arearranged over the entire circumference of the stator 5. The projections19 are in this case arranged on a circumferential ring 29A extendingradially inwardly into the flow duct 7 and, for example, are connectedin one piece to said circumferential ring. The circumferential ring 29Ahaving the projections 19 surrounds the rotor 5 over the entirecircumference and forms part of a stator casing, not illustrated in anymore detail. For greater clarity, the field distribution of the magneticfield B is illustrated only in a part region of the guide blade region15. The polarity is selected such that the magnetic north pole N isformed at the projections 19 of the stator 5, so that the flux linesemerge at the projections 19, penetrate inwardly through the flow duct 7predominantly in the radial direction and enter the interior of therotor 3 through the rotor surface 41. Owing to the ions 27 in theflowing action fluid A, a charge current through the flow duct 7 isachieved, which interacts with the magnetic field in the magnetic guideblade region 15 and in the magnetic moving blade region 17 (FIG. 4), andin this case an inductive effect is to be noted. Thus, on account of thecharge current itself, similarly to a live conductor in a magneticfield, a magnetic field is generated which is superposed on the externalmagnetic field B in the flow duct. As a result, along the chargecurrent, in the case of constructive superposition, field regions withincreased flux line density are formed and, at the same time, in thecase of a destructive superposition, corresponding field regions with alower flux line density are formed. Since magnetic flux lines tend to beshortened, this leads to a deflection of the charge current from thefield region with increased flux line density to the field region withlower flux line density (Lorenz Law).

FIG. 4 shows, in a similar illustration to FIG. 3, a sectional view ofthe axial direction through a magnetic moving blade region 17 along thesectional line IV-IV of the turbomachine illustrated in FIG. 1.

For the spatial delimitation of the magnetic field B of the magneticmoving blade region 17, the magnetic moving blade region 17 has aplurality of radially outwardly extending projections 21 which arearranged over the entire circumference of the rotor 3 on acircumferential ring 29B of the rotor 5. The circumferential ring 29Bserves for the spatial delimitation, in particular in the axialdirection, of the magnetic field B in the magnetic moving blade region17 and extends radially outwardly. Here, as compared with the magneticguide blade region 17 (FIG. 3), the polarity of the magnetic field B isselected such that magnetic north poles N are in this case formed at theprojections 21 of the rotor 5, so that the flux lines emerge at theprojections 21, penetrate outwardly through the flow duct 7 in theradial direction and enter the interior of the stator 3 through thestator surface 43. By means of the projections 19, 21, a concentrationof the magnetic flux lines, that is to say an increased intensity of theradial magnetic field B, in the guide blade region 17 and in the movingblade region 15 is achieved, and the interaction of the magnetic field Bwith the charge current accompanying it due to the movement of the ions27 is thereby restricted to these local regions. By virtue of the fielddistribution in the guide blade region 17 and in the moving blade region15, magnetic deflection planes (guide planes and moving planes) or, onthe basis of the axial dimension, deflection disks are produced.

The provision of such magnetic deflection planes for the chargedparticles 25, 27 or the ion-containing action fluid A by means of themagnetic field B is in this case really similar in its action to aconventional blade cascade:

In the case of an axial turbomachine 1, as discussed here by way ofexample, there is, for example, a deflection of the predominantly axialflow of action fluid A in a flow with both an axial and a tangentialcomponent, this being because, by virtue of the Lorenz force F_(L) (FIG.2), a tangential component is imparted to the charged particles 25, 27perpendicularly to the flow direction as a result of interaction withthe magnetic field B.

This deflection is associated with a conversion of pressure energy ofthe action fluid A into kinetic energy, in a similar way to a guideblade cascade of a conventional turbine. In the same way, it ispossible, from a flow of the action fluid A with an axial and atangential component, to achieve a conversion into a predominantly axialflow, with kinetic energy being converted into mechanical work, in asimilar way to a moving blade cascade of a conventional turbine.Consequently, in a way similar to conventional turbines, a suitablemagnetic field configuration with a magnetic field B in the flow ductgenerated spatially and, if appropriate, in time by the magnet 9 allowsa progressive expansion of the action fluid A, along with theacquisition of mechanical work which can be transmitted in the form ofrotational energy to the rotor 3 on account of the magnetically inducedangular momentum change to be noted, so that said rotor rotates at anangular speed ω.

In order to illustrate the analogy of the MHD turbomachine 1 to aconventional turbine, for example a steam turbine, FIGS. 5 and 6 showthe pressure profile 49 and the velocity profile 51 for a conventionalreaction turbine with conventional blading (FIG. 5) and for aturbomachine 1 with MHD blading. The path profile 37, shown in FIG. 5,of a particle, for example of a gas or steam molecule, through theturbine steps, which are formed in each case from a conventional guidewheel 45 and moving wheel 47, is to a great extent similar in quality tothe path profile 37 of an ion 27 when the latter runs through themagnetic steps of the invention, which are composed in each case axiallyin succession from a magnetic guide blade region 15, a field-freeinterspace 35 and a magnetic moving blade region 17. This analogy isalso to be found in the pressure profile 49 and in the velocity profile:

The pressure profile 49 of the action fluid A expanding in the axialdirection is plotted in the middle part graph of FIGS. 5 and 6 againstthe axial running length L (FIG. 6) and against the number of steps(FIG. 5). The pressure p is plotted on the Y-axis of the coordinatesystem and the axial running length L or the number of steps is plottedon the X-axis. In both part graphs, the pressure p decreases, regularly,in the form of steps along the X-axis, and, particularly in the magneticguide blade region 17 and moving blade region 15, a marked pressure dropis to be noted, according to the pressure profile, over the conventionalguide blade row 45 and moving blade row 47. The pressure p isapproximately constant in between.

The velocity profile 51 of the action fluid A expanding in the axialdirection is plotted in the lower part graph of FIGS. 5 and 6 againstthe axial running length L (FIG. 6) and against the number of steps(FIG. 5). The velocity c is plotted on the Y-axis of the coordinatesystem and the axial running length L or the number of steps is plottedon the X-axis. What is meant by the velocity c is in these cases what isknown as the absolute velocity, a quantity which is generally known inturbine construction.

In the two part graphs, the velocity c alternates equally between aminimum value c_(min) and a maximum value c_(max). Thus, the velocity cover a guide blade row 45 rises from the minimum value c_(min) to themaximum value c_(max), reaches a plateau-shaped virtually constantsegment and subsequently, over the following moving blade row 47,decreases again from the maximum value c_(max) to the minimum valuec_(min). This velocity profile 51 is also to be found exactly in thecorresponding lower part graph of FIG. 6, where these effects on thevelocity c also occur during the axial expansion of the action fluid Athrough a magnetic guide blade region 15, interspace 35 and the magneticmoving blade region 17.

In a block diagram, FIG. 7 shows diagrammatically, in greatly simplifiedform, the arrangement of the process functions D1 to D7 and processdevices by the example of a steam turbine, using magnetohydrodynamic(MHD) blading of the invention. First, preceding process functions D1and D2 are provided, which are carried out before the actual MHD processin a turbomachine 1, here a steam turbine with a steam process. Thepreceding process functions comprise, in the first place, the supply ofheat into the action fluid A, here water or steam. The heating of theaction fluid in process step D1 may in this case take place, forexample, in a boiler, a steam generator boiler. Subsequently, aconventional steam turbine process takes place (optionally) in D2, theheated action fluid A flowing through a conventional steam turbineblading so as to perform work and at the same time partially expanding.To generate an ion-containing action fluid A, the ionization ofparticles in the action fluid A is provided in process step D3. For thispurpose, an ionization device 23 is implemented, which generates ions 27(cf. also FIG. 1) with sufficient density in the action fluid A, forexample by means of radiation ionization or of electron collisionionization. In process step D4, the actual MHD process is carried out.The ion-containing action fluid A flows through the flow duct 7, adefined magnetic field B being generated in the flow duct 7, the ionsbeing deflected in the magnetic field. The rotor 3 of the MHDturbomachine 1 is set in rotation as a result of the deflection of theions 27 owing to interaction with the magnetic field. Ions 27 may inthis case also be generated in MHD process step D4 by the ionization ofparticles in the action fluid A during the flow of the latter throughthe flow duct 7. If necessary, the MHD process step D4 is followed by aprocess step D5 in which the action fluid is purified of harmfulsubstances in a recombination process and/or in a catalytic process. Forthis purification step, for example, a recombination device 31 isimplemented.

The following process steps D6 and D7 are of the conventional type:thus, a conventional steam turbine process again takes place(optionally) in D6, the still hot action fluid A flowing through aconventional steam turbine blading so as to perform work and at the sametime expanding further. As high an overall efficiency of the entiresteam turbine plant as possible can thereby be achieved. Finally, inprocess step D7, the discharge of heat from the largely expanded actionfluid A is carried out in a condenser 53.

In a further block diagram, FIG. 8 shows diagrammatically, in greatlysimplified form, the arrangement of the process functions G1 to G7 andprocess devices by the example of a gas turbine, usingmagnetohydrodynamic (MHD) blading of the invention. First, a precedingprocess function D1 is provided, which is carried out before the actualMHD process in a turbomachine 1, here a gas turbine with a gas turbineprocess. The preceding process function G1 first comprises thecompression of an action fluid A, here of compressor air in aconventional compressor part. Subsequently, in G2, an MHD compressorprocess optionally takes place, in which an ion-containing action fluidA is generated by means of an ionization device 23 and is compressed inan MHD process in an MHD compressor with MHD blading. Thereafter, instep G3, the action fluid A compressed in this way is heated. Theheating of the action fluid A in process step G3 may in this case becarried out, for example, in the combustion chamber of the gas turbine,the compressor air from process step G2 being burnt together with afuel, and hot combustion gas thus being available as action fluid A forthe following process step G4.

To generate an ion-containing action fluid A, in process step G4, theionization of particles in the action fluid A is provided. For thispurpose, an ionization device 23 is implemented, which generates ions 27(cf. also FIG. 1) with sufficient density in the action fluid A, forexample by means of radiation ionization or of electron collisionionization. In process step G4, at the same time, the actual MHD processis carried out. The ion-containing action fluid A flows through the flowduct 7, a defined magnetic field B being generated in the flow duct 7,the ions 27 being deflected in the magnetic field. The rotor 3 of theMHD turbomachine 1, here an MHD gas turbine, is set in rotation as aresult of the deflection of the ions 27 owing to interaction with themagnetic field. Ions 27 may in this case also be generated additionallyin MHD process step G4, even before entering the flow duct 7, by theionization of particles in the action fluid A. If necessary, the MHDprocess step G4 is followed by a process step G5 in which the actionfluid A is purified of harmful substances in a recombination processand/or in a catalytic process. For this purification step, for example,a recombination device 31 is implemented. The following process steps D6and D7 are of a conventional type: thus, in G6, a conventional gasturbine process again takes place (optionally), the still hot actionfluid A, that is to say the hot gas, flowing through a conventional gasturbine blading so as to perform work and at the same time expandingfurther and cooling. As high an overall efficiency as possible of theentire gas turbine plant which comprises process steps G1 to G7 canthereby be achieved. Finally, in process step G7, the discharge of heatfrom the already largely expanded and cooled action fluid A is carriedout in a waste heat recovery boiler 55, another heat exchanger device ora chimney.

It remains to be said, in summary, that, as was shown, an MHD bladingfor a turbine machine can mean that both magnetic guide blade regions 15and magnetic moving blade regions 17 are implemented in a turbomachine 1by the magnetohydrodynamic effect being utilized. It is, however, alsopossible to combine a conventional guide wheel or guide blade row 45with a magnetic moving blade region 17 or else a magnetic guide bladeregion 15 with a conventional moving wheel or moving blade row 47. Inthis respect, therefore, “mixed steps” with MHD and conventional bladingcan also be implemented in a turbomachine 1 or in a process plant with aturbomachine 1. In this case, it is expedient, for the operation of theturbomachine 1, to precede the MHD process with the ionization device23, so that a sufficiently high density of ions 27 in the action fluidis ensured even upon entry into the flow duct 7 of the turbomachine 1.Reionization can be carried out continuously or repeatedly by means ofsuitable ionization devices 23 in the course of the process, that is tosay during the flow of ion-containing action fluid A through the flowduct 7. A recombination device 31 may be provided for purification afterthe flow through the MHD blading or, if appropriate, even along thelatter, particularly in the case of devices or components in the flowduct 7 which require protection. In the latter instance, it is advisableto carry out the renewed ionization of action fluid A in the flow duct 7before the action fluid A flows into the next magnetic guide bladeregion 15 or moving blade region 17.

1. A turbomachine, comprising: a rotor; a stator; a flow duct forguiding an action fluid, the action fluid provided for driving therotor; and a magnet for generating a predetermined magnetic field in theflow duct arranged on the stator, and the magnetic field is orientedradially relative to a rotation axis of the rotor.
 2. The turbomachineas claimed in claim 1, wherein the magnetic field changes itsorientation by 180° at least one time along the rotation axis.
 3. Theturbomachine as claimed in claim 1, further comprising: a magnetic vaneregion extending along the rotation axis, the magnetic guide bladeregion having a uniform orientation of the magnetic field; and amagnetic blade region extending along the rotation axis, the magneticblade region having a uniform orientation of the magnetic field, whereinthe magnetic field in the blade region is contrarily oriented relativeto magnetic field in the vane region.
 4. The turbomachine as claimed inclaim 3, wherein the magnetic blade region is arranged downstream of themagnetic vane region relative to a flow direction of the action fluid.5. The turbomachine as claimed in claim 3, wherein a number of magneticvane regions and blade regions are arranged alternately along therotation axis.
 6. The turbomachine as claimed in claim 3, wherein thestator comprises a first circumferential ring for limiting the magneticfield in the magnetic vane region, the first circumferential ringextending radially inwards relative to the rotation axis.
 7. Theturbomachine as claimed in claim 3, wherein the rotor comprises a firstprojection projecting radially inwards relative to the rotation axis forlimiting the magnetic field in the magnetic vane region, the firstprojection included in the magnetic vane region.
 8. The turbomachine asclaimed in claim 7, comprising a plurality of radially inwards extendingfirst projections arranged across the entire circumference of thestator.
 9. The turbomachine as claimed in claim 3, wherein the rotorcomprises a second circumferential ring for limiting the magnetic fieldin the magnetic blade region, the second circumferential ring extendingradially outwards relative to the rotation axis.
 10. The turbomachine asclaimed in claim 3, wherein the rotor comprises a second projectionprojecting radially outwards relative to the rotation axis for limitingthe magnetic field in the magnetic blade region, the second projectionincluded in the magnetic blade region.
 11. The turbomachine as claimedin claim 10, comprising a plurality of radially outwards extendingsecond projections arranged across the entire circumference of therotor.
 12. A turbomachine, comprising: a rotor; a stator; a flow ductfor guiding an action fluid, the action fluid provided for driving therotor; a magnet for generating a predetermined magnetic field in theflow duct; and an ionization device for generating charged particlesincluded in the action fluid.
 13. The turbomachine as claimed in claim12, further comprising a recombination device for the recombiningcharged particles included in the action fluid.
 14. A method ofoperating a turbomachine having a rotor, a stator and a flow duct forguiding an action fluid, the action fluid including ions, the methodcomprising: generating a magnetic field; directing the magnetic fieldthrough the flow duct; passing the action fluid through the flow duct;and deflecting the ions by the magnetic field, wherein the ions includedin the action fluid are generated by ionization of the action fluidbefore the action fluid enters the flow duct.
 15. The method as claimedin claim 14, wherein the rotor is rotatably actuated by the deflectedions.
 16. The method as claimed in claim 14, wherein the magnetic fieldis oriented radially relative to a rotation axis of the rotor, and atangential velocity component of the action fluid is exclusivelyaffected by the magnetic field.
 17. The method as claimed in claim 14,wherein the magnetic field is oriented radially relative to a rotationaxis of the rotor, and an orientation of the magnetic field alternatesalong a flow direction of the action fluid.
 18. The method as claimed inone of claim 14, wherein the magnetic field is controlled regarding itsshape or behavior over time.
 19. The method as claimed in claim 14,wherein the ions are generated by ionizing fluid particles included inthe action fluid while the action fluid flows through the flow duct. 20.The method as claimed in claim 14, wherein the ions are generated usinga collision ionization mechanism.
 21. The method as claimed in claim 14,wherein the ions are generated using a radiation ionization mechanism.22. The method as claimed in one of claim 14, wherein the action fluidis purified using a recombination process or a catalytic process forextracting harmful substances from the action fluid.
 23. The method asclaimed in claim 22, wherein the action fluid is purified before theaction fluid enters the flow duct.
 24. The method as claimed in claim22, wherein the action fluid is purified after the action fluid exitsthe flow duct.